WIP 75 - Sex-specific effects of routine early administration of hydrocortisone on survival without bronchopulmonary dysplasia in extremely premature infants.

Poster Number: WIP 75
Publication Number: WIP 75.707

Background: Bronchopulmonary dysplasia (BPD) is an aberrant reparative response to both antenatal injury and repetitive postnatal injury to the developing lung, and the most frequent complication of prematurity. Sex is an important determinant in the development of BPD, with some studies reporting worse outcomes in males. The anti-inflammatory action of steroids has been leveraged for the management of BPD. The PREMILOC trial demonstrated increased survival without BPD at 36 weeks postmenstrual age (PMA) in extremely preterm infants after prophylactic low-dose hydrocortisone administration, without any evidence of adverse neurodevelopmental consequences.

Objective: The goal of this study is to measure the sex-specific impact of early hydrocortisone use in preterm infants on the incidence of survival without BPD at a tertiary care NICU.

Design/Methods: This is a retrospective cohort study (EVMS IRB # 21-07-WC-0189) being conducted on infants admitted to the NICU at the Children’s Hospital of the King’s Daughters in Norfolk, VA from 6/2014- 6/2020. Starting in 2017, the BPD Prophylaxis Protocol was instituted per the PREMILOC paradigm (0.5mg/kg hydrocortisone q12 x 7d, followed by 0.5mg/kg q24 x 3 days) for infants ≤ 29 weeks gestational age and/or birthweight ≤ 1000g. The primary outcome is survival at 36 weeks PMA without BPD (stratified by the 2019 Jensen criteria). Secondary outcomes include need for mechanical ventilation at DOL 10, vasopressor use and the incidence of a hemodynamically significant PDA. Outcomes will be compared to historical controls admitted to the NICU before the implementation of the BPD prophylaxis protocol. All statistical tests will be performed using SPSS.26 (Chicago, IL). A logistic regression model will be used to assess the impact of risk factors on primary and secondary outcomes. All outcomes will be stratified by sex to measure differences. Thus far, we have compiled 100 (62%) pre-intervention and 60 (38%) post-intervention subjects. This sample will be expanded for analysis prior to April 2024 by further data collection from a pool of 996 subjects.